Multi-stage steam turbine

ABSTRACT

A multi-stage steam turbine, about the size of an automobile engine, is contained in a lightweight, separable housing, the housing having a driven shaft in the lower half with the bladed rotors thereon. Each disc-like rotor is encircled by an individual, cylindrical housing which forms a turbine blade chamber therewith and the housings are supported on the lower half of the casing. Each successive stage is of decreasing volume. Only the first stage rotor has blades on both side faces; the first stage blades are driven by multiple solenoid controlled steam jets; and the other rotors are driven by steam from preceding stages.

Migneault ted States Patent [1 1 1 1 MULTl-STAGE STEAM TURBINE [76] Inventor: Maurice Migneault, 69 Bowers St.,

Nashua, N.1-1. 03060 [22] Filed: Oct. 28, 1971 [21] Appl. No.: 193,397

[52] US. Cl. 415/66, 415/108, 415/198, 415/199 A [51] Int. Cl. F0ld 1/24 [58] Field of Search.....415/60-66, 108, 198, 199 A [56] References Cited UNITED STATES PATENTS 761,226 5/1904 Hedlund 415/198 798,757 9/1905" Young 415/198 845,762 3/1907 Crary 415/198 860,905 7/1907 Davidson 415/198 912,882 2/1909 Oraker 415/198 934,497 9/1909 Barre 415/198 951,162 3/1910 Wedekind 415/66 1,109,133 9/1914 Melchers 415/198 1,418,704 6/1922 Green 415/198 1,511,517 10/1924 Henderson. 415/66 1,190,622 7/1916 Bashor 415/60 Primary Examiner--C. J. Husar Attorney-Pearson & Pearson [5 7] ABSTRACT A multi-stage steam turbine, about the size of an automobile engine, is contained in a lightweight, separable housing, the housing having a driven shaft in the lower half with the bladed rotors thereon. Each disc-like rotor is encircled by an individual, cylindrical housing w ishf m e yrbias ble ?she etth e t and the housings are-supported on the lower half of the casing. Each successive stage is of decreasing volume. Only the first stage rotor has blades on both side faces; the first stage blades are driven by multiple solenoid controlled steam jets; and the other rotors are driven by steam from preceding stages.

10 Claims, 10 Drawing Figures PAIENIEn sm new SHEET 1 OF 2 RADIATOR Fly. 4.

PAIENIEn mH I 3,758,224-

' SHEEIBOFZ 1 MULTI-STAGE STEAM TURBINE BACKGROUND OF THE INVENTION Multi-stage steam turbines have long been known and usually are built on a large scale for powering generators. The stages usually consist of a set of bladed rotors spaced along a shaft and separated by a corresponding set of stator blades. The path of the steam is circuitous in first encountering the curved blades of the first stage rotor, then being reversed by the curve of the first stator blades to encounter the curved blades of the second rotor, and so on through the turbine. Each successive rotor and stator increases progressively in diameter to compensate for the decrease in pressure and expansion of the steam.

Such prior art turbines tend to be heavy, to require firm mountings to prevent excessive vibration and to rotate in the range of 25,000 rpm so that considerable speed reduction mechanism is required to use the same, for example in a locomotive or other vehicle.

To date, while there has been considerable publicity concerning steam turbines designed for automobile use to reduce pollution, the proposed engines have not yet been placed in general use, perhaps because-they attempt to follow prior art teachings too closely.

SUMMARY OF THE INVENTION In this invention themulti-stages are not containedin a single chamber with steam progressing axially through a stack of increasingly larger rotor and stator blades. Instead, each stage consists of a disc-like rotor, enclosed in a separate, individual, cylindrical casing, and the states are free of stator blades. The fresh steam is discharged from a pair of oppositely disposed banks of solenoid valve controlled steam jet orifices against the cup-shaped blades extending radially from center to circumference on each opposite side face of the first stage rotor.

The spent steam, instead of passing through stator blades to the next rotor, is collected circumferentially from the first stage casing in an outlet aligned with the steam jets and guided in flat, thin conduit means to a narrow, elongated radial slot orifice in the wall of the next casing to encounter the cup-shaped blades on the adjacent face of the second rotor. In an outlet aligned with this slot, the spent steam is collected in a similar manner and delivered to the third rotor, and similarly to the fourth rotor, whereupon it passes into a condenser, also within the separable housing.

Preferably, each successive rotor and stator is of reduced diameter, and reduced volumetric capacity, contrary to prior art teaching, and preferably a normally fully open, spring biased clapper, or damper, valve is interposed in the conduit between each stage, the valve closing halfway when steam pressure is reduced.

Preferably also, rather than all stages beingmounted on a single shaft, a pair of shafts are rotatably mounted,

in parallelism, across the lower half of the housing, and 1 two stages are mounted on each, in staggered, interleaved formation, to reduce the overall gine. v

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings: v FIG. 1 is a diagrammatic plan view, in half section of width of the enthe preferred embodiment, of the invention with double shafts; I I

FIG. 2 is a side elevation of the turbine shown in FIG.

FIG. 3 is a side elevation of the face of a bladed turbine rotor of the invention;

FIG. 4 is a diagrammatic side elevational view, in half section, of another embodiment of the invention using a single shaft;

FIG; 5 is a side elevation of the first and second stages, and FIG. 6 is a similar view of the second and third stages of the turbine of FIGS. 1 and 2;

FIGS. 7, 8, 9 and 10 are diagrammatic perspective views showing the successive stages of the turbine of FIG. 4.

DESCRIPTION OF THE PREFERRED EMBODIMENT In the drawings, the multi-stage turbine 20 is shown diagrammatically to include a portable housing 21 of lightweight material such as aluminum. Preferably, as shown in FIG. 4, the lower portion 22 is separable from the upper portion 23 along the line 24. The upper portion 23 may be a coverpivoted at 24 and the lower portion may have solid walls, or comprise a skeletonized frame since it is not conventional steam enclosure, or chamber. 7

The housing 21 includes a pair of oppositely disposed walls, 25 and 26, which preferably are upstanding, parallel,,side walls connected by a bottom wall 27 and by opposite end walls 28 and 29. v

Rotatably mounted in-walls 25 and 26, in suitable bearings, is shaft means 31, referably consisting of a pair. of rotor shafts 32and 33, in parallelism'and extending across the housing 21 with a set of intermeshed gears 34, 35 and 36 connecting adjacent ends to cause .the two shafts to rotate at the same speed. Gear 35 is revolvable on shaft 37 and suitable power take-off sheaves or gears 38 and 39 are provided on the opposite ends of the shafts which project outside the housingv 21.

The turbine 20 includes multiple stages designated first stage 41 and succeeding stages 42, 43 and 44. The condenser is designated 45.

Each stage consists of a bladed turbine rotor, such as 46,- 47, '48 and 49, of disc-like configuration and having opposite diametrical faces 51 and 52, the rotors each I being spaced along, and fast to, the'shaft means 31.

Each stage alsoincludes a hollow, cylindrical casing,-

such as 53, 54, 55 and 56,- each encircling and sealing one of the turbine rotors and each having an axially extending integral tube, or sleeve, such as 57, 58 59 or 61, encircling-the shaft and supported by the side walls 25 and ,26. v I

The rotor 46 of first stage 41 is provided, with a plurality of circumferentially spaced, radially extending, identical turbine blades 62 on each opposite face 51 and 52 thereof. The rotors 47; 48 and 49 of the succeeding stages 42, 43 and 44 have blades 62 only on the face thereof adjacent the steam orifice, which orifice is on the side closest to the preceding stage.

Each blade 62 includes a radially extending wall 63, normal to the side face 51 or 52 to which it is fixed, and extends from proximate the center of the rotor at an integral inner end wall 64 to proximate the periphery at an integral outer end wall 65. The end walls 64 and 65 extend substantially circumferentially to define a semicupped configuration, there being no outer side wall because the steam jets are directed sidewise into thev full length of the cup-like blades. Inclined vanes 66 are provided at the inner ends of the blades to form impeller means which clears the axial portion of each casing of steam and directs spent steam outwardly for collection near the circumference.

Steam jet means 67 includes a suitable steam pipe 68 leading from a source of steam 69, such as a flash boiler or the like, to first stage 41. The term steam, as used herein, is intended to include any similar fluid, such as mercury or any other liquid denser than water, which may prove useful or practical. Steam pipe 68 leads to a header, or manifold, 71 or 72, each on an opposite side of the lower part of casing 53, each header having at least four radially spaced jets 73, 74, 75 and 76, each controlled by one of a set of four solenoid actuated control valves 77, 78, 79 and 81 (FIG. Steam may thus be simultaneously directed against the full height of the blades on each opposite side of the first rotor for maximum power, or by suitable control circuits not shown, selected valves may be closed to produce less steam pressure for slower speed.

Steam conduit means 82 includes a plurality of thin, flat pipes, such as 83, 84 and 85, each leading generally tangentially from a peripheral, circumferential location, such as at 87, on one stage to the adjacent side wall, such as 88, of the casing of the next stage to terminate in a narrow, elongated, radially extending orifice, such as 89, for directing the steam against the blades of the rotor therewithin.

Preferably, a plurality of spring relief valves, such as 91, 92, 93 and 94, are each interposed in one of the pipes 83, 84 or 85, each between and adjacent pair of stages. Each valve 91, 92, 93 or 94 is normally fully open under full steam pressure, but is closed half way upon any reduction in such pressure to automatically control the volume of steam delivered to the successive stages. The valves 91, 92, 93 and 94 may be of any well known clapper, or damper, type having a pivoted closure, biased toward closed position by a spring.

The condenser 45 is mounted within the housing 21 and includes a casing 95 having a series of showers 96 in the upper wall fed from a radiator 97, the radiator 97 being fed from a suitable sump and pump 98 in the bottom of the condenserrThus the waste steam in condenser 45 is convertedto liquid by the cooling effect of the radiator. The radiator supplies cool shower water to condense the steam and a portion of the liquid is returned to the steam source 69 for reuse.

As shown in FIGS. 4 and 7-10, the stages 41, 42, 43

1 and 45 can be all mounted on the same shaft, such as 32, and the conduit means and valve means mounted as shown, all within the scope of the invention.

It should be noted that in FlG.'1 the stages 41 and 43 are interleaved and staggered relative to stages 42 and 44 to reduce the dimensions of the housing and that the adjacent walls of the individual housings could be formed by a single wall, if desired, especially in the embodiment of FIG. 4. Preferably, there are about 16 blades on each side face of the first stage rotor and only about four blades on the single faces of the succeeding rotors.

It should also be noted that the peripheral outlet 99 of first stage 41 is aligned with, and in the direct flow path of, the jets of the headers 71 and 72 so that the initial impact of the steam is expended on the blades and the steam then continues on with lessened force into outlet 99 and through pipe 83 to again impact the blades of the next stage 42.

As shown in FIG. 6, the casings, such as 54 and 55, are split at 24 and joined by bolts 100 for ease of access. The casing 53 is preferably about 12 inches in diameter and the successive casings 54, 55 and 56 are l 1, l0 and 9 inches in diameter, respectively. Blades 62 in stage 41 are each about one-quarter inch wide, while the blades of the other stages are one-half inch in width.

What is claimed is:

1. In a steam turbine of the multiple stage type, the combination of:

a housing having a pair of oppositely disposed walls;

shaft means extending between, and rotatably mounted in said walls, and projecting outside said housing;

multiple turbine stages within said housing, each including a disc-like turbine rotor fast on said shaft means and having turbine blades on at least one side thereof and a hollow cylindrical casing enclosing'said rotor and forming a blade chamber therewith;

steam jet means leading from a source of steam into the said blade chamber on each opposite side of the casing of a first said stage for driving the rotor therewithin; and

steam conduit means connecting the blade chamber of the casing of said first stage to successive stages and thence to said condenser for directing said steam to the bladed rotors in each said stage;

said conduit means collecting steam peripherally from each chamber and delivering the same sidewise into the next successive chamber.

2. A steam turbine as specified in claim 1, wherein:

each successive stage after said first stage has a rotor with substantially less blades than the rotor of the first stage.

3. A steam turbine as specified in claim 1, wherein:

the rotor of said first stage has blades on each opposite side face thereof and the rotors of each successive stage have blades only on one side face thereof.

4. A steam turbine as specified in claim 1, wherein:

said steam jet means includes a plurality of jet orifices, each having a solenoid valve for opening and closing the same;

said orifices being jets radially spaced along the side of said rotor for driving the same;

whereby selected orifices may be controlled by an electric circuit.

5. A steam turbine as specified in claim 1, wherein:

said steam conduit means includes a plurality of spring relief valves, each located between an adjacent pair of stages and each normally fully open at full steam pressure but adapted to close half way under reduced pressure for automatically controlling the volume of steam delivered to said stages.

6. A steam turbine as specified in claim 1, wherein:

said steam conduit means comprises a plurality of flat, thin pipes each extending from the circumference of one said casing to a narrow, elongated, radially extending orifice in the side of the next casmg.

7. A steam turbine means as specified in claim 1, wherein:

the blades of each of said turbine rotor each comprise a radially extending wall normal to a side face of said rotor and terminating at each opposite end in an integral end wall extending substantially circumferentially of said rotor to define a semicupped configuration free of a side wall adjacent said steam jet means.

8. In a steam turbine of the multi-stage type:

at least four stages each, including a turbine rotor, having turbine blades on at least one side face thereof, said rotor being rotatable within a stationary cylindrical casing which forms a turbine blade chamber therewith;

means delivering steam to the first said stage against the side of said rotor for driving the blades thereon;

means conducting said steam from said first stage to each successive stage for driving the rotors thereof, said means collecting steam peripherally from one stage and delivering steam sidewise into the next successive stage; and

valve means in said steam conducting means for controlling the fiow of steam therethrough.

9. A turbine as specified in claim 8, wherein:

said steam conducting means comprises a plurality of thin, flat conduits each leading from a tangential, peripheral location on one stage to the adjacent side wall of the next stage and terminating therein in a narrow, elongated, radially extending orifice adapted to drive the blades of the rotor in said next successive stage.

10. A turbine as specified in claim 8, wherein:

each said rotor is of disc-like configuration with cupshaped blades extending radially therefrom from proximate the center to proximate the periphery thereof;

said steam delivering means includes a plurality of jets in opposite side walls of the casing of the first stage, directing steam in a predetermined, linear path into said blades and generally tangentially of said casing; and

saidsteam conducting means includes an outlet in the periphery of said first stage casing, aligned with said steam jets and in the linear path of said steam for collecting said steam and delivering the same into the casing of the next successive stage. 

1. In a steam turbine of the multiple stage type, the combination of: a housing having a pair of oppositely disposed walls; shaft means extending between, and rotatably mounted in said walls, and projecting outside said housing; multiple turbine stages within said housing, each including a disc-like turbine rotor fast on said shaft means and having turbine blades on at least one side thereof and a hollow cylindrical casing enclosing said rotor and forming a blade chamber therewith; steam jet means leading from a source of steam into the said blade chamber on each opposite side of the casing of a first said stage for driving the rotor therewithin; and steam conduit means connecting the blade chamber of the casing of said first stage to successive stages and thence to said condenser for directing said steam to the bladed rotors in each said stage; said conduit means collecting steam peripherally from each chamber and delivering the same sidewise into the next successive chamber.
 2. A steam turbine as specified in claim 1, wherein: each successive stage after said first stage has a rotor with substantially less blades than the rotor of the first stage.
 3. A steam turbine as specified in claim 1, wherein: the rotor of said first stage has blades on each opposite side face thereof and the rotors of each successive stage have blades only on one side face thereof.
 4. A steam turbine as specified in claim 1, wherein: said steam jet means includes a plurality of jet orifices, each having a solenoid valve for opening and closing the same; said orifices being jets radially spaced along the side of said rotor for driving the same; whereby selected orifices may be controlled by an electric circuit.
 5. A steam turbine as specified in claim 1, wherein: said steam conduit means includes a plurality of spring relief valves, each located between an adjacent pair of stages and each normally fully open at full steam pressure but adapted to close half way under reduced pressure for automatically controlling the volume of steam delivered to said stages.
 6. A steam turbine as specified in claim 1, wherein: said steam conduit means comprises a plurality of flat, thin pipes each extending from the circumference of one said casing to a narrow, elongated, radially extending orifice in the side of the next casing.
 7. A steam turbine means as specified in claim 1, wherein: the blades of each of said turbine rotor each comprise a radially extending wall normal to a side face of said rotor and terminating at each opposite end in an integral end wall extending substantially circumferentially of said rotor to define a semi-cupped configuration free of a side wall adjacent said steam jet means.
 8. In a steam turbine of the multi-stage type: at least four stages each, including a turbine rotor, having turbine blades on at least one side face thereof, said rotor being rotatable within a stationary cylindrical casing which forms a turbine blade chamber therewith; means delivering steam to the first said stage against the side of said rotor for driving the blades thereon; means conducting said steam from said first stage to each successive stage for driving the rotors thereof, said means collecting steam peripherally from one stage and delivering steam sidewise into the next successive stage; and valve means in said steam conducting means for controlling the flow of steam therethrough.
 9. A turbine as specified in claim 8, wherein: said steam conducting means comprises a plurality of thin, flat conduits each leading from a tangential, peripheral location on one stage to the adjacent side wall of the next stage and terminating therein in a narrow, elongated, radially extending orifice adapted to drive the blades of the rotor in said next successive stage.
 10. A turbine as specified in claim 8, wherein: each said rotor is of disc-like configuration with cup-shaped blades extending radially therefrom from proximate the center to proximate the periphery thereof; said steam delivering means includes a plurality of jets in opposite side walls of the casing of the first stage, directing steam in a predetermined, linear pAth into said blades and generally tangentially of said casing; and said steam conducting means includes an outlet in the periphery of said first stage casing, aligned with said steam jets and in the linear path of said steam for collecting said steam and delivering the same into the casing of the next successive stage. 